Suspension insulator



l 11, 927 YJMMPECK i sUsPENSIQN INSULATR Fiied Feb. 11. 1924 tra Patented oct. 11,1927'.

UNITED STATE 1,645,447 PATENT OFFICE.

JOHN M. '.PECK, OF LIMA, NEW YORK, ASSIGNOR T0 THE PORCELAIN INSULATOR' CORPORATION, OF LIMA, NEW YORK,

A CORPORATION. oF NEW Yoan.

SUSPENSION INSULATOIR.

. Application led February 11, 1924. Serial No. 691,971.

withstand both electrical and mechanical loads more eectively.

`In a more particular aspe t, the ob]ect of the invention is to secure the bolt member to the insulating body portion in such a manner as to distribute the stresses equally over the entire insulating surface surrounding the bolt member, instead of concentrating the eect of such stresses over a relatively small area of such surface, as in prior constructions.

Another object of the invention is to reduce the destructive effect from expansion, by interposing a flexible member in a cement body between the bolt member and the body portion. y

W'ith these ends in view, the invention comprehends the construction that lwill appear clearly from the f llowing description when read in conjunction with the accompanying drawing, the novel features being pointed out in the claims following the description.v

In the drawing:

Figure l is a sectional view `of a suspension insulator showing the application of a preferred embodiment of my invention, and

, Figure V2 is an enlarged sectional vview through the load-distributing device.

The invention may be carried out practically in anumberof different ways and includes in generalla load-distributing member, preferably in the form of a thimble of thin flexible metal having its interior and exterior surfaces corrugated or of other :suite able irregular formation, and located in a body of cementitious material between the bolt member and porcelain body portion.

AIn the construction shown, 1 designates the body portiony ofla conventional type of .suspension insulator provided with a cap in the form of an eye- 2 and bolt member 3,

invention relates to insulators, and

`surface of the porcelain bolt that is received 'in an opening in the lpody 1 and fixedly secured to the body porion.

4 designates a flexible thimble of thin metallic material, preferably co-extensive with the opening lin theinsulator, and having a closed inner end fitting against the porcelain at the top of the opening. The end of the thimble may be separated fromthe porcelain surface by'a thin film of resilient cement, and is secured in place by a body of Portland cement 5 occupying the space between lthe exterior side walls of the thimble and the interior sanded surface 6 on the porcelain body portion.

The thimble 4 functions primarily to increase'the bearing surface of the porcelain body and distribute the stresses, result-ing from both mechanical and electrical loads, equally over the entire adjacent surface of the porcelain body portion, so that an eX- cessive .stress is not concentrated at any one given point. This greatly increases the strength of the insulator under practical operating conditions as well as its period of usefulness.

v This result may be effected by other forms of load-distributing devices, to transmit the load from the bolt member to the adjacent surface of the porcelain body equally, and the thimble just described is merely one eX- ample of different possible means of accomplishment.

Where a metal thimble is used,

in the porcelain body portion, it is preferably provided with a series of lateral co1'- rugations 7 throughout `the length of the thimble and affording irregular surfaces both cxteriorly and interiorly.. This effects an interlocking engagement with the cement binder,.and also serves to. distribute the stresses evenly from top to bottom of the body surrounding the opening for the bolt member.

The parts are held togetherb suitable cementitious material' interpose between the porcelain body portion Aand theV thimble, preferably throughout the len yth of the thimble, and also between the t imble and bolt member for a portion of such length. Preferably I employ Portland cement between the vbody portion and thimble and a lead alloy between the bolt member and thimble, as designated at: 8. There is a certain amount of contraction in the alloy, uponk lowingl claima I claim: Y In an insulator, the combination with a lhollow body portion, of a load distributing within the'intent \of.v. my improvement or the scope of the fol- ""s1gned my naine.

thimble arranged therein and co-extensive in length with the opening in the body portion, the thimble having Aa series of lateral corrugations throughout its length, a body of cement between the thimble and the body portion. a bolt member arranged within the thimble having an unobstructed c lindrical body and an enlarged head, the body and head of the bolt member being s aced from the sidesof the thimble, and a ody of cement located bet-Ween the bolt member and the inner surface of the thimble and acting by engagement with the underside of the head to hold the bolt member in the thimble. 4 In witness whereof, I have hereunto JOHN M. PECK. 

